Among them is Debbie Halvorson, who lost to Jackson in the March primary last year, but garnered 29 percent of the vote.

A flurry of candidates submitted candidacy petitions over the weekend, filed along with 1,256 signatures or more. Joyce Washington, who ran for US Senate in 2004, announced Sunday that she would enter the race, as did Robin Kelly. She announced Monday via Twitter that she'd raised more than $200,000 from 500-plus individual donors.

Of the 22 candidates, five are Republican: Lenny McAllister, Beverly Reid, Paul McKinley, James H. Taylor Sr., and Eric Wallace.

A complete list of the candidates is posted on the State Board of Elections web site.

A special primary will be held on February 26 and the general election is scheduled for April 9.